Centrifugal casting machine



Dec. 30. 1924.

J. B. LADD CENTRIFUGAL CASTING MACHINE Fil p 13, 1921 .10 Sheets-Sheet 1 ATTORNEY 10 Sheets-Sheet 2 .II NR 5 M Q a IIVVENTOR ATTORNEY \J. B. LADD CENTRIFUGAL CASTING MACHINE Filed Sept. 13, 1921 J. B. LADD CENTRIFUGAL CASTING MACHINE 10 sheets-sheet 5 Filed Sept. 13, 1921 v mk A ITO/WE) Dec. 30. 1924.

J. B. LADD CENTRIFUGAL CASTING MACHINE Filed Sept. 13, 121

l0 Sheets-Sheet 4 INVEA/TO JW 5' M ATTORNEY Dec. 30. 1924. 11,521,244

' -J. B. LADD CENTRIFUGAL CASTING MACHINE Filed Sept. 13, 1921 10 Sheets-Sheet 5 ATTOlM/EV J.B.LADD

CENTRIFUGAL CASTING MACHINE l0 Sheets-Sheet 6" Filed Sept. 13, 1921 ATTORNEY 10 Sheets-Sheet v m N NW w W w 1. H1

J. B. LADD CENTRIFUGAL CASTING MACHINE Filed Sept. 13, 1921 Dec. 30. 1924. 1,521,244

J. B. LADD CENTRIFUGAL CASTING MACHINE Filed Sept. 15, 1921 I0 Sheets-Sheet a INVE/VTUR ATTORNEY Dec. 30, l 924.

J. B. LADD CENTRIFUGAL CASTING MACHINE Filed Sept. 13, 1921 l0 Sheets-She t 9 ///IIIII. 1

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A NORA/EV J. B. LADD CENTRIFUGAL CASTING MACHINE Filed Sept. 13, 1921 l0 Sheets-Sheet 10 Patent Dec. 30, 1924.

JAMES B. LADD, OF ARDMORE, PENNSYLVANIA, ASSIGNOR' TO UNITED STATES CAST IRON PIPE & FOUNDRY COMPANY, OF BURLINGTON, NEW JERSEY, A CORPORATION OF NEW JERSEY.

cnn'mrrtrcan casmne MAC INE;

Application filed September is, 1921. Serial No. 500,331.

To all whom it may concern:

Be it known that I, Junie B LADD, a citizen of the United States of America, and resident of Ardmore, in the county of Montgomery and State of Pennsylvania, have invented a certain new and useful Improvement in Centrifugal Casting Machines, of which the following is a true and exact description, reference being had to the ac companying drawings, which form a part thereof.

My invention relates to centrifugal casting machines of the type described in the Ger man patent to Briede, No. 242,307 issued January 4, 1912, that is to say a centrifugal casting machine comprising a relatively movable rotating mold and runner so operated that the molten metal flowing through the runner into the mold is delivered into the mold in a helical stream. The object of my invention is to generally improve the construction and efliciency of such a casting machine and particularly my object is, in the first place, to provide improved means for securing in the runner during the greater part of the casting operation a stream of molten metal of constant volume and velocity and with this object in view my invention consists in providing in connection with the mold and runner a pouring ladle or receptacle which remains in a substantially fixed position during the pouring of the metal, and from which the metal is poured into the runner and in which the metal is automatically maintained at a constant level and head.

Another object of my invention is to provide for the heating of the runner when it is withdrawn from the mold whereby it is prevented from cooling the iron poured into it and a more uniform temperature and fluidity of the iron is secured. The heating of the runner also reduces the amount of scull or dead iron left in the runner after each cast.

Another object of my invention is to provide an anti-frictional support whereby the runner can be supported .within' the mold. In the German patent above referred to the runner is provided near its outer end with a ring which rests upon the mold'and serves to support the end of the runner therein.

- This ring also serves as a limitstop for the flow of metal in the mold and as a means by which the casting is pushed out of the mold, and a further object of my invention is to provide an improved construction of such a ring and for its automatic attachment to and detachment from the runner and from the end of the mold whereby, as will be explained, it is made more practical and efficient.

Another object of my invention is to provide means for the ready adjustment of the inclination of the runner whereby the speed of the flow of metal therethrough and'into the mold can be regulated.

Still another object of my invention is to provide means at the end of the runner whereby the longitudinal flow of the metal can be arrested and the metal delivered downward onto the mold.

Still another object of my invention is a construction of the runner and its supports so that the rupner' can be partly revolved on its supports and its contents dumped out and also the protection of the mechanism lying beneath, the runner from contents dumped from the runner by interposing a cover plate beneath the runner and above said mechanism.

Still another feature of my invention is the combination with a casting machine of the type in questionv of a periscope by means of which the flow of metal into the mold can be observed from the point where the general operation of the mechanism is mostreadily controlled, and the special construction of this periscopic device so that it can be swung out of operative position to permit the free movement of the mold.

Still another feature of my invention is the provision of automatic mechanism whereby the motion of the mold with respect to the runner will begin at a definite time interval after the beginning of the delivery of metal into the runner so as to allow time for the metal to flow through the runner into the mold and to fill the end of the mold before the mold begins its longitudinal movement.

Another object of my invention is the provision of automatic mechanism whereby the speed of motion of the mold with reference to the runner can be slowed down after the flow of metal into the runner is stopped and while the metal remaining in the runner is flowin into the mold in diminished quantity an at diminished speed. By properly adjusting the relative speed of movement of the mold and runner with reference to the diminishing flow of metal I utilize a larger amount of the metal coming from the ladle than has heretofore been practicable.

Another object of my invention is the provision of improved stop mechanism for arresting the relative movement of the mold with reference to the runner at both ends of its travel and at selectively difierent points.

A further object of my invention is the provision of supports for receiving the casting whenpushed out of the mold and of automatic means whereby said supports are shifted out of the path of the mold during the motion of the mold in the casting operation.

While the above are the leading objects of my invention there are other features which will be best understood as described in connection with the drawings-which illustrate a machine embodying my invention and in which Figure 1 is a plan view of my improved machine.

Figure 2 is a side elevation of the machine with the mold in the position shown in Fig. 1.

Figure 3 is a similar side elevation with a mold shown in the position in which it is moved over the runner.

Figure 4-. is a side elevation similar to that shown in Fig. 3 but with the mold and runner and the framing supporting the mold and runner, shown in =vertical section along the center of the machine.

Figure 5 is a sectional view similar to that of Fig. 4 with a mold shown retracted from the runner and the pouring and reservoir ladles also shown in section.

Figure 6 is a face view of the ladles and their supporting and actuating mechanism viewed as on the line 6-6 of Fig. 5.

Figure 7 is a view on an enlarged scale of a part of the mechanismshown in Figs. 1, 2 and 3.

Figure 8 is a. cross sectional View on the line 8--8 of Fig. 5.

Figure 9 is a cross sectional v ew on the line 9-9 of Fig. 5.

Figure 10 is a cross sectional view on the line 1010 of Fig. 5.

' Fi e 11 is a cross sectional view on the line 1111 of Fig. 5.

Figure 12 an end view taken as on the line 1212 of Fig. 5.

Figure 13 is a View 1313 of Fig. 4, looking toward the left.

Figure 14 is a plan view of the end of the mold and of the end of the runner with taken as on the line surrounding the mold removed and with the ring which is engaged by and which supthrough the end of ,the mold, its water.

jacket casing, the ring, and the runner, all shown in vertical central section.

Figure 16 is an end view of the appliances shown in Fig. 15, looking toward the left.

Figure 17 is an end view of thebaflle plate secured tothe end of the runner as shown in Fig. 15.

Figure 18 is a sectional view ofa detail of the construction shown in Figs. 14 and 15; drawn on an enlarged scale.

Figure 19 is a sectional elevation of'the end of the runner and baflle plate showing a slight modification in the construction shown in Figs. 15 and 16.

Figure 20 is an end view of the devlce shown in Fig. 19.

Figure 21 is a detail shown partly in sec tion of a preferential time escapement device which is not illustrated in the preceding figures by reason of their small size.

F igure 22 is an end view of the mechanism shown in Fig. 21.

Figure 23 is a sectional elevation of the mold, runner and modified ring supporting anti-frictional means in the relative posltions which they occupy at theclose of a casting operation.

Figure 24: is a side elevation of the'mechanism shown in Fig. 2 with the addition of the preferential device not illustrated 1n the former figures by means of which the motion of the mold with reference to the runner can be slowed up at the close of the cast ng operation and while the runner is draining into the mold.

Figure 25 is an enlarged detall of the construction shown in Fig. 24, and

Figure 26 is a detail showing the mold and framework in sectional elevation and illustrating the arrangement of o eratlve parts indicated in Figs. 10, 24 an 25.

A indicates the base on which the framing of the machine '-is supported. A, A, are the frames extending upward from the base A and on which the pouring and reservoir ladles are supported. B indicates the framing supporting the mold and runner; B, B', tracks on which run' the cylinders supporting the mold which, in the construction illustrated and by preference, constltutes the movable element of the relatively movable parts made up of the moldand runner, although obviously, as in the case of the German patent above referred to, the

runner can-be moved backward and forward in a stationary mold. B B are brackets extending out from the side of the frame B and serving as supports for the slida'ble stop rod H. B B and b are brackets supporting the rotatable rod or shaft indicated at N C indicates the lower and C the upper section of the casing or water jacket surrounding the mold and supporting it in position. The lower section of the mold is provided with supportin wheels C which run it over the tracks at C C1, are supporting wheels for the mold journalled, as shown best in Fig. 11, on the inside of the casing. C C indicate piston rings located in annular grooves in the end casing section 0, C, fitting on the ends of the mold to prevent the escape of water from the water jacket. C is a pipe leading into one end of the casing section C- and through which water is introduced into the casing. As shown this pipe is provided with an extension 0* running parallel to the line of motion of the machine and passing through a stufl'ing box C", Fig. 9, into a parallel pipe section indicated at C see Fig. 8, and conveniently attached, as shown, to the cylinder F.

C, best shown in Figs. 10, 15 and 23, is

an upwardly extending chamber leading from the end of the casing section C having, as shown, an open top and a drain pipe C by which the cooling water can freely flow ofl. D is the mold supported in the casing C, C, and of generally cylindrical form through, as illustrated and for use as a bell mouth pipe mold, the mold is provided with a bell mouth D see Figs. 4. and 5, against the end of which fits the removable head plate E which may carry a bell core such as is indicated at D The rear end of the mold is shown as provided with a gear indicated at D through which and the gear indicated at E the mold is driven by a motor indicated at E.

As a means for moving the mold with reference to the "runner, any convenient mechanism can, of course, be employed but I prefer to use the cylinder, indicated at F. from the piston working in which, not shown in the drawings, extends a. piston rod F secured to the rear end of the easing supporting the mold andwhich is referably formed with an upwardly curved end as indicated at F 3 for the purpose to be hereafter described. As a means for-actuating the piston in the cylinder F fluid is introduced through the pipe G into a threeway valve, indicated at G, and through either of the pipes G or G to the respective ends of the cylinder F. The cylinder end not connectedwith the source of fluid under pressure is, through the valve, connected with the exhaust indicated at g and .it will be understood that in the useof this device it is important that the fluid under pressure should be kept under constant pressure as uniformity of movement is exceedingly important in the operation of the machine. The valve G is, as shown, actuated by a lever (Sr and attached to this lever is a toothed segment G see Figs. 7 and 8, which engages a circular rack H formed on or attached to a sliding rod H supported in the bearings B provided with a handle H by which it can be turned in its bearings and having at its left hand end a stop lever H, see Fig. 10, which comes in contact with the fingerh attached to the casing C, when the mold is moved to a predetermined position over to the right and by shifting the rod H and its toothed rack H moves the segment G of the valve G to out off the flow of fluid into the left hand end of the cylinder 1'. The stop lever H is, as shown in Fig. 10, broadened out at its end so that any rocking motion of the rod H will not move it out of operative relationship to the finger If. Also secured to the rod H are the stop levers H H, which, as shown in Fig. 8, are set at an angle so that by-turning the rod H either one or the other can be brought into position to be engaged by the stop finger k and in this way the movement of the mold toward the runner can be increased to push the casting clear of the mold.

By preference I provide mechanism not only for arresting the movement of the mold as above described but also for slowing down its rate of movement towards the end of the casting operation, and I do this so that I may cut ofl the supply of metal to the runner before the casting is completed and at the same time make available a large part or all of the metal remaining in the runner after the supply to it is cut off and the metal is passing into the mold in reduced volume and velocity. This slowing up of the motion of the mold can be conveniently effected, as shown in Figs. 24, 25 and 26, by attaching to the end of the rod H a curved lever H pivoted to the frame, as indicated at H, and operated upon by a cam contacting surface, such as is indicated at it, such cams being attached to the casing section C and operating on the lever H at the latter part of the arresting. motion ,of the casting and mold.

I is therunner which is, generally speaking, in the form of an open top trough with an upwardly inclined receiving end indicated at I and preferably flared, as best shown in Fig. 13. The runner is formed with a rearwardly extending bearing indicated at I and with a counterweight I and actuating lever 5 The hearing I is sup ported on a standard I through a verticaL.

ly movable support I which can be moved up and down by means of a bolt I and nut I so as to adjust the inclination of the runner and thus regulate the speed with which the metal flows through it. At the bottom of the delivery end of the runner the I bearing surface I is provided which, when the runner is retracted from the mold, as shown, for instance, in Fig. 15, rests on the "roller I". The lower part of the end of the runner is also preferably beveled, as shown at I, to enable it to freely enter the ring to be hereafter described.

In, order to arrest the longitudinal motion of the metal running from the runner into the mold and deflect it downward to the mold I provide at the end of the runner a baflle plate or hood as indicated at 1 see Figs. 15 and 17, which mav extend entirely beyond the side walls of the runner as shown in the above figures or may have extensions of the side wall, as indicated in Figs-19 and 20,. where 77 indicates the extensions of the side walls of the runner. I I, are stiff springs secured to the sides of the runner and adapted to enter and frictionally engage the latches T when the runner is thrust into the ring K. I, I are projections also secured to the sides of the I runner, and which, when the ring K passes 7 indicated at J, and in this ring fits another ring K supported in the ring J by the balls indicated at K and having preferably a flared end as indicated at K 'The outer portion of the ring J is formed with an annular recess, as indicated at J which recess, when the ring is in the position shown in Fig. 14, is indicated by fingers T and the latches T having inwardly projecting fingers T and attached to the rods T which are pressed inwardly by springs indicated at T the arrangement being such that the ring is anchored in position at'the end of the mold D until the latches are thrust back on the runner by the cams I which occurs after the end of the runner has entered the ring K and the springs I have taken a strong, frictional grip upon it.

Considering next the means used for heating the runner, L indicates a gas pipe pivotally supported on the brackets B and from which extend upward pipes L, L connecting with the pipes L L*, which extend under and over the runner as shown in Figs. 2 and 8; the pipes are in the pos'ttion shown in full lines in Fig. 8 and they can be retracted, as shown in dotted lines, be-

fore the mold is being moved over the runner, and, at '5 I have indicated that the burner should extend under the lower side pressure secured.

supported on top of the framing B and between the runner and the mechanism lying beneath the runner.

for inducing and arresting the flow' of metal therefrom into the runner and having means whereby a uniform level can be maintained in the ladle and a consequent uniform flow The special ,mechanism shown in the drawings and by which the above described results are secured consists of a bottom pour ladle N which is supported on a lever N pivoted at U and provided with a counterweight N The arrangement being such that the ladle is held at a definite point with the lever arms N practically horizontal when the ladle is charged with molten metal to its full capacity. As shown,

the counterweight is provided with projecting pins 11 over which extend slightly elongated loops R of a limit stop consisting of a rod or rods R attached to the standard A at R. The ladle N should, for the best results, have a capacity several times that of the casting to be made in the rotary mold. The ladle is formed with a bottom pour orifice N at its bottom and preferably with a cover a in which is formed an opening N for the reception of metal from a reservoir 1 and through which, as shown, extends the gas pipe N by which gas can be induced to maintain a flame on top of the meta l. N is a stopper by which the bottom pour orifice is opened and closed and this stopper,-as shown, is connected to a vertically guided rod N guided in the brackets N N and raised and lowered by means of the toggle levers N N", which are actuated by the link N", the bell'crank lever N the link N the lever n and rock shaft N which is turned to raise or lower the stopper by the lever N and which is provided with another lever N which lies in operative relation'to a cam plate N iwhich is attached to the casing C, C, as shown in Figs. 2 and 10, so that it contacts with the lever N during the latter part of the casting operation and rocks the shaft N in a direction to bring about the closing of the opening in the bottom pour ladle. By preference the rock shaft N is'also provided with a crank arm 11 at its left hand end, as shown in Figs.- 3, 21 and 22, so as to fill the time escapement device shown and described.

P is a reservoir ladle, as shown, of the bottom pour type having a stopper P for opening and closing its delivery orifice and this stopper is connected by a guide rod P and a link P attached at its lower end to a lever arm 41. attached to and moving with the levers N.

While I have in mind to provide automatic means for regulating the starting of the longitudinal movement of the mold, it is highly desirable that the flow of metal into the end of the mold at the beginning of the casting operation should be observed and the motion of the mold when necessary controlled so as to secure just the right amount of metal for the formation of the bell or end of the mold before longitudinal motion is imparted to themold and to enable 'an operator situated at the head of the machine to judge the flow of metal, I provide my machine with periscope consisting of a tube Q, pivotally supported in the stand ards Q so that it may be regulated, having a sight lass indicated at Q at its right hand end and an arm indicated at Q so arranged that when turned down it will enable the operator to look directly into the left hand end of the mold when the mold is in the position shown in Fig. 4. The rotatable periscope is provided with a lever arm Q by which it can be rocked into and out of operative position and with a counterweight Q by which it is balanced.

It is dsirable that rests or supports should be provided to receive the cast pipe when it is pushed out of the mold. These supports must also be retracted to clear the mold when it is moved toward the left and I provide for this requirement by means of the rock shafts S, S, best shown in Figs. 4, 5, 11 and 12, which are supported in bearings in the frame B and provided with torsion springs S which tend to move them in one direction. To the shafts S I secure the hubs S and supports S which, by the action of the springs, are normally held in the posi-' tion indicated in Fig. 4 but which, when the mold moves toward the left, are pressed down by the curved end F of the rod F and held below the mold in the position shown in Fig. 5.

To describe now the operation of my.im-' proved machine, and assuming the parts to be initially in the position shown in Figs. 2 and 5, the first thing to be done is to heat the runner to a sufficiently high degree to avoid the risk of chilling the metal which is about to be run into it. This is accomplished by means of the burners L L which at this time are brought to the position shown in Fig. 8, and which are retracted to the position shown in dotted lines before the mold is moved forward over the runner and the next thing to be done is to move the mold toward theright until it reaches the position shown in Fig. 4. This is readily accomplished by moving the lever Gr of the valve against the inner face of the ring K so as to take a strong, frictional grip upon it.

Continued motion of the-mold brings the fingers T of the latch T into contact with the cams I pushing apart the latches T until the jaws T release their hold on the ring J after which the rings remain stationary on the end of the runner and support the end of the runner, the ring K beingpof course, stationary with regard to rotation and the ring J which is in frictional contact with the rotating mold D, rotating with it. At the end of this movement the parts are in the position indicated in Fig. 4e and the periscope is turned from the position it has heretofore occupied, that shown in Fig. 5, to its operative position, that shown in Fig. 4.

The operator next turns the rock shaft N by means of the lever N and through the lever a, link N bell-crank N rod N forces the toggle joint links N into a vertical line and thus lifts the guide rod N and the stopper N and opens the bottom pour'channel in the ladle to its full extent. It will be understood that before beginnlng to pour from the ladle N the ladle is charged to its full maximum extent and is count-erbalanced by the counterbalance weight N As metal flows out of the ladle it is forced upward by the counterbalance N moving the lever arm N upwardly and, through the rod P the guide rod P raises the stopper P in the bottom pour reservoir l The extent to which the pouring orifice 1n the reservoir P is open depends on the extent of the upward motion of the ladle N and it will readily be understood that the device I have illustrated can and will have the efiect of maintaining a practically constant level of melted metal in the ladle N.

It will be understood, of course, that it takes an appreciable interval of time for the stream of metal coming from the ladle N to pass through the runner 1 into the mold and it will also be obvious that when a bell mouth pipe is being cast it will take also an appreciable time to fill the bell end of the mold, and it is not until the metal is 1n full flow into the mold and the bell end filled, that the travel of the mold toward the left should begin. The flow of metal lnto the mold of course can be observed through the periscope and the valve lever G turned to operate the valve to a position to start I themold toward the left just at the proper the pouring operatio time, but while manual control cannot perhaps be entirely avoided, it is, where the umform flow of metal is provided for as I provide for it, practical to provide means for automatically starting the mold in longitudinal motion and at the proper time. Such a means I have shown in Figs. 3, 21 and 22, whereby rocking of the shaft N through the lever arm n opens the valve 0 admitting fluid pressure to the right side of the time escapement cylinder 0 with the result of moving the piston O and rod 0 backward with regulated s eed until the rod 0 clears the lever arm' and the lever arm 0 actuating on the stop 0 on the rod Hshifts this rod toward the ri ht and through the rack H and segment (1% shifts the valve G to a position to start the left hand movement of the mold. Obviously, by throttling the exhaust O the speed of movement of the time escapement cylinder can be regulated.

As the mold continues its motion toward the left with uniform speed and the metal is delivered into it from the end of the runner in uniform volume and velocity the metal is laid in the revolving mold in a helix-like coil, the adjacent coils fusing freely together but not having time to flow laterally to any great-extent. In this-connection it will be noted that the provision of the bafile plate I is important as tending to check the longitudinal motion of the metal at the end of the runner and result in its flowing downward practically at right angles to the surface of the mold, so .that

so far as the momentum of the metal is concerned there is but little tendency to impart a longitudinal flow to it when it reaches the mold.

In the construction illustrated I use the J as the means of pushing the cast pipe out ofthe mold and to properly perform the function it must during the right hand movement of the mold approach more closely the end of t mold than during or it may even be best tohave it partly clear the end of the mold. To provide for the movement I secure to rod H the two angling fingers H,

H either of which can be turned to position to contact with finger k by turning the rod H. When either finger H or H contacts with finger k the rod H is moved toward the right and through the rack H and segment G5 turns the valve G to a position to out 01f the flow of pressure fluid to the cylinder F and bring the mold .to a rest in the desired position with reference to ring J. t I

It will be obvious that the fingers H, H, and H 5 should all be adjustable lengthwise on the rod H so that the motion of the mold can be arrested at selective points. Ob-

viously the motion of the mold toward the" left is arrested through the contact of the stop finger h? with the lever H attached at the left hand end of the rod H and operating to close the valve admitting pressure It is obviously desirable to provide automatic means for cutting off the flow of molten metal from the ladle N at a proper time and this is effected in my machine by the action of the cam N on the lever N see Fig. 10, the pressing outward of the lever N rocking the shaft N in adirection to draw the toggle levers l N outward, as shown in Fig. 6, and cut off the flow from the ladle.

When the flow of the metal from the ladle is cut oil before the casting has been completed it is obvious that the metal remainmg in the runner will flow into the mold with decreasing volume and. velocity and consequently the end of the casting will be thinner if the rate of motion of the mold remains the same. It is, therefore, advisable to slow up the motion of the mold after the flow of metal from the ladle has ceased at a rate corresponding to the decreasing rate'at which metal from the-runner flows into the mold and this I provide for by securing to the mold casing a cam k opcrating upon a curved lever H pivoted at H and secured, as shown in Figs. 24 and 25, to the end of therod H. It will, of course, be evident that as the rod H is gradually drawn toward the left it will effect a gradual closing of the valve G and a gradual diminution of the pressure fluid admitted to the. cylinder F and this can readily be regulated.

The casting being complete it is next necessary to extract the casting from the mold and in my machine this is accomplished .by moving :the mold toward the right with the result that the ring J presses a inst the end of the casting, as shown in Flg. 23, and being held in fixed position on the runner either by direct attachment to it, as shown in Fig. 23, or by detachable means such as are shown in Figs. 14 and 15. holds the casting-stationary while the mold moves over it and at the end of the motion of the mold the casting is. entirely free thereof and in my construction is received on the supports S, as shown in Fig. 4, these supports'rising to receive the casting as the mold moves from above them and being retracted on the reverse movement of the mold as I have already described.

After the extraction of he casting the -mold' is again moved toward the left until metal and then turned back to operative position, heated by the gas burners and the operation goes on as before, and it will be observed that I provide the cover M and other appliances described to prevent the cleanings from the runner falling into the space between the sides of the frame B.

Having now described my invention, what I claim as new and desire to secure by Leters Patent, is:

1. In a centrifugal casting machine comprising a rotatable mold, a runner for delivering molten metal 'to the mold and means for imparting a relative longitudinal motion to the, runner and mold, the combination therewith of a ladle stationary during pouring for delivering a stream of molten metal to the runner and means for maintaining a substantially uniform level of metal in the ladle whereby a constant volume and velocity is maintained in the stream issuing therefrom.

2. I11 a centrifugal cast-ing machine comprising a rotatable mold, a runner for delivering molten metal to the mold, and means for imparting a relative longitudinal motion to the runner and mold, the combination therewith of a ladle stationary during pouring for delivering a stream of molten metal to the runner, said ladle having a holding capacity several times that of the volume of the casting to be made and means for maintaining a substantially uniform level of metal in the ladle whereby a constant volume and velocity is maintained in the stream issuing therefrom.

3. In a centrifugal casting machine comprising a rotatable mold, a. runner for delivering molten metal to the mold and means for imparting a relative longitudinal motion to the runner and mold, the combination therewith of a ladle stationary during pouring for delivering a stream of molten metal to the runner and means actuated by variations in the weight of metal in the ladle for maintaining a substantially uniform level of metal in the ladle whereby a constant volume and velocity is maintained in the stream issuing therefrom.

4. In a centrifugal casting machine comprising a rotatable mold, a runner for delivering molten metal to the mold and means for imparting a relative longitudinal motion to the runner and mold, the combination therewith of a bottom pour ladle for delivering a stream of molten metal to the runner and means for maintaining a substantially uniform level of metal in the ladle whereby a constant volume and velocity ismaintained in the stream issuing therefrom.

5. In a centrifugal casting machine comprising a rotatable mold, a runner for delivering molten metal to the mold and means for imparting a relative longitudinal motion to the runner and mold, the combination therewith of a ladle for delivering a stream of molten metal to the runner, means for supporting said ladle whereby it is permitted to moi e up and down with variations in its weight, a reservoir for molten metal arranged to deliver its metal to the said ladle and means for controlling the flow of metal from the reservoir to the ladle actuated by the movements of the ladle so as to maintain a constant level of metal in the ladle.

6. In a centrifugal casting machine comprising a rotatable mold, a runner for delivering molten metal to the mold and means for imparting a relative longitudinal motion to the runner and mold, the combi nation therewith of means for heating the runner located to operate when the runner is withdrawn from the mold.

7. In a centrifugal casting machine comprising a rotatable mold, a runner for delivering molten metal to the mold and means for imparting a relative longitudinal motion to the runner and mold, the combination therewith of means for heating the runner, comprising retractable gas burners.

8. In a centrifugal casting machine comprising a rotatable mold, a runner for delivering molten metal to the mold and means for imparting a relative longitudinal motion to the runner and mold, the combination therewith of a ring slidable in-the mold and serving as a support for the delivery end of the runner, and anti-friction means interposed between the ring and runner.

9. In a centrifugal casting machine comprising a rotatable mold, a runner for delivering molten metal to the mold and means forimparting a relative longitudinal motion to the runner and mold, the combination therewith of a ring slidable in the mold and serving as a support for the delivery end of the runner, a second ring revolvable within the first ring and means for securing the second ring in the runner.

10. In a centrifugal casting machine comprising a rotatable mold, a runner for delivering molten metal to the mold and means for imparting a relative longitudinal motion to the runner and mold, the combination therewith of a ring slidable in the mold and serving as a support for the delivery end of the runner, antifriction means interposed between the ring and runner, means whereby said ring is engaged by the runner during its relative backward and forward motion with relation to the mold. and means for disengaging the ring from the runner and holding the ring within the end of the mold when the runner passes out of the mold.

11. In a centrifugal casting machine comprising a rotatable mold, anopen ended lull runner for delivering molten metal to thelongitudinal motion to the runner and mold, the improvement which consists of means for independently adjusting the inclination of the runner.

13. In a centrifugal casting machine a relatively movable mold and runner in combination with power mechanism for moving-the same, means for stopping the moving element at the designed limits of its movements comprising a stop engaged when the runner is fully wlthout. the mold and two stops adjustable so that one or the other is engaged as the runner moves into the mold and motion is arrested at selective points.

14. In a centrifugal casting machine a relatively movable mold and runner in combination with power mechanism for moving the same and means for varying the speed of motion of the relatively moving elements whereby the speed of motion of the positivelymovable element is varied at definite points of its path of motion.

15. In a centrifugal castin machine having a relatively movable mo (1 and runner and power mechanism for moving the same, means for feeding molten metal to.

the runner, means for inducing and stopping the flow of metal to the runner and automatic means for actuating said flow con-v trolling device to stop the flow of metal when the moving element reaches a deter-' the runner and means for causing the ower mechanism to start moving the mol and rumier relative to eachother at a definite time after the flow of metal to the runner begins.

- 17. In a centrifugal casting machine comprising a relatively movable mold and runner the combination therewith of means for feeding a uniform stream of metal to I the runner, automatic means for cutting off the flow of metal to the runner,-means for moving the moving element and means for slowing down the motion of said mov- '-ing element after the flow of metal to the runner is cut 0E and while the metal in the runner is flowing therefrom in a diminishing stream.

- 18. In a centrifugal casting machine comprising a longitudinally movable mold and a stationary runner, supports for the casting arranged to receive the casting when p the mold is over the runner and automatic means for moving the supports out of the way of the mold when it is moved away from the runner.

19. In a centrifugal pipe casting machine comprising a runner -fixed in. position, means for feeding molten metal to the runner, a longitudinally movable pipe mold and control mechanism for regulating the movements of the mold, the combination therewith of a periscope having a sight opening located adjacent to the control mechanism and its observing enddirected into the distant end of the mold.

20. In a centrifugal casting machine com prising a relatively movable mold and runner the combination therewith of a periscope whereby the flow of metal into the mold can be observed, said periscope being supported so that it can be moved to clear the mold.

21. Ina centrifugal casting machine comprising a longitudinally stationary. runner, a longitudinally movable mold and mechanism for moving the mold located .be-

neath the runner, a cover plate located between the runner and said mechanism.

22. In a centrifugal casting machine comprising a rotatable but longitudinally stationary runner, a longitudmally movable.

mold and mechanism for moving the mold located beneath the runner, a cover plate located between. the runner and said mech-" anism. 

